The present invention is generally directed to a method of forming a heat sink device for dissipation of thermal energy which is generated by electronic devices such as semi-conductors and generally directed to the apparatus for carrying out the method. The present invention is more specifically directed to a method of and apparatus for forming a heat sink device which consists of a solid base portion and a plurality of spaced parallel cooling fins which are fixed to the base and which extend transversely of one broad surface of the base.
Many types of electronic devices generate heat during their operation. This heat must be dissipated to avoid damage to the device. Some of these electronic devices have power-handling limitations due to their inability to dissipate internally-generated heat. A heat sink is any body of metal or equivalent material which is placed in contact with an electronic device for absorbing heat from the device and for dissipating the heat to the atmosphere by convection and/or radiation.
As a rule, heat sinks are constructed of metals which have a high coefficient of thermal conduction such as aluminum and copper and alloys of these two metals. The heat sinks are formed into shapes which are conducive to a high rate of conductive and convection of heat.
The most commonly used type of heat sink consists of a generally rectangular solid base and a plurality of spaced parallel fins which are fixed to the base and which extend transversely of one broad surface of the base. The opposite broad surface of the base is applied to the electronic device to be cooled. The heat sink is mechanically attached to an electronic device by a clamping device such as a resilient spring clip.
Heat sinks of the type described above are made in a number of ways. The heat sink can be made by extruding a continuous strip having the desired heat sink configuration and then severing individual heat sink units from the extrusion. This method has severe limitations with respect to fin height, fin thickness and fin density. Another method of forming the heat sink is to machine the fins from a solid block of metal. This method is labor intensive, time consuming and expensive. These and other difficulties experienced with the prior art devices have been obviated by the present invention.
It is, therefore, a principle object of the invention to provide a method of forming a heat sink body by casting a base to one end of a row of spaced parallel plates or fins.
Another object of the invention is the provision of a method of forming a heat sink body by die casting a base to one end of a row of spaced parallel plates or fins.
A further object of the present invention is the provision of apparatus for casting a heat sink base to one end of a row of spaced parallel plates or fins.
It is another object of the present invention to provide apparatus for die casting a base onto one end of a row of spaced parallel plates or fins.
A still further object of the invention is the provision of apparatus for die casting a base directly onto one end of a row of parallel spaced fins which is adjustable for a range of fin heights.
It is a further object of the invention to provide a heat sink which is formed by casting a solid base to one end of a group of parallel spaced plates.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.